Observation of a Polar Compound with Halide Ordering in the Compositional Series (CH <sub>3</sub> NH <sub>3</sub> ) <sub>2</sub> Te(Br <sub> <i>x</i> </sub> Cl <sub> 1– <i>x</i> </sub> ) <sub>6</sub>
Single-crystal samples of compounds in the series (CH<sub>3</sub>NH<sub>3</sub>)<sub>2</sub>Te(Cl<sub>1-<i>x</i></sub>Br<sub><i>x</i></sub>)<sub>6</sub> were produced with counter-diffusion crystal growth in silica gels, and new crystal structures are determined using single-crystal X-ray diffraction. With increasing Br content, the structure transitions from <i>P</i>3̅<i>m</i>1 to <i>P</i>6<sub>3</sub><i>mc</i> to <i>R</i>3̅<i>m</i> and finally to <i>Fm</i>3̅<i>m</i>. The compound with x≈0.068 adopts the polar <i>P</i>6<sub>3</sub><i>mc</i> space group, and the structure has partially ordered Cl<sup>-</sup> and Br<sup>-</sup> ions. The crystals of this compound show distinct piezoelectric domains with different responses by Piezoresponse Force Microscopy (PFM), confirming their polar structure.
Authors
- Prajna Bhatt
- Anna Regoutz (ORCID: https://orcid.org/0000-0002-3747-3763)
- Roxy Lee (ORCID: https://orcid.org/0000-0001-7845-0093)
- Robert G. Palgrave (ORCID: https://orcid.org/0000-0003-4522-2486)
- Robin Perry (ORCID: https://orcid.org/0000-0002-1825-2201)
- Avishek Dey (ORCID: https://orcid.org/0000-0003-3256-1825)
- Yuhan Liu (ORCID: https://orcid.org/0000-0001-7019-3379)
Institutions
- London Centre for Nanotechnology (GB)
- University of Oxford (GB)
- Istituto Officina dei Materiali (IT)
- University College London (GB)
- Technical University of Denmark (DK)
Publication Details
- Journal
- Inorganic Chemistry
- Published
- 2025-10-22
- DOI
- https://doi.org/10.1021/acs.inorgchem.5c03380
- Primary Topic
- Solid-state spectroscopy and crystallography
- Type
- article
- Field-Weighted Citation Impact
- 0.00